package collection;

import java.util.ArrayList;
import java.util.Collection;

/**
 * Collection接口的演示
 */

public class CollectionDemo {
    public static void main(String[] args) {
        Collection c = new ArrayList();
        c.add(new Point(1, 2));
        c.add(new Point(3, 4));
        c.add(new Point(5, 6));
        c.add(new Point(7, 8));
        c.add(new Point(9, 0));
        c.add(new Point(1, 2));
        System.out.println(c);

        Point p = new Point(1, 2);
        boolean contains = c.contains(p);
        System.out.println("是否包含："+contains);//true

        /*从当前集合中删除给定元素o的equals()比较为true的元素
        若存在重复只删除一次
         */
        c.remove(p);
        System.out.println(c);
        Collection cc = new ArrayList();
        Point pp = new Point(1, 2);
        cc.add(pp);//将pp添加到cc中----将pp的引用装到了cc中
        System.out.println("pp:"+pp);
        System.out.println("cc:"+cc);
        pp.setX(100);
        System.out.println("pp:"+pp);
        System.out.println("cc:"+cc);
















        /*
        Collection c = new ArrayList();
        c.add("one");
        c.add("two");
        c.add("three");
        c.add("four");
        c.add("five");
        //集合重写了Object的toString()方法，返回格式如下：
        //[元素1.toString(),元素2.toString(),元素3.toString(),....]
        System.out.println(c);
        System.out.println("size:"+c.size());//5，输出集合的元素个数
        //isEmpty()判断集合是否为空集（size()为0表示空集）
        System.out.println("是否为空集"+c.isEmpty());//false
        c.clear();//清空集合
        System.out.println("集合已清空");
        System.out.println(c);
        System.out.println("size:"+c.size());//0
        System.out.println("是否为空集："+c.isEmpty());//true

         */


    }
}
